US20070095095A1

US20070095095A1 - Chemical heat pump working according to the hybrid principle related application

Info

Publication number: US20070095095A1
Application number: US10/580,326
Authority: US
Inventors: Göran Bolin
Original assignee: ClimateWell AB
Current assignee: ClimateWell AB
Priority date: 2003-12-08
Filing date: 2004-12-08
Publication date: 2007-05-03
Also published as: SE527721C2; KR20070029120A; CN100416181C; JP2007513319A; WO2005054757A1; ZA200604416B; CN1890514A; BRPI0417389A; SE0303304D0; SE0303304L; EP1716370A1; IL175733A0; AU2004295656A1

Abstract

In a chemical heat pump installation two identical main units are provided, each one including a reactor and one condenser/evaporator integrated in the same container (100). One main unit is charged while the other one e.g. produces cooling. Large energy amounts are consumed in the switching operation when the unit that has been charged is to be cooled and the unit that has produced cooling is to be heated. To reduce these amounts of energy each of reactor and condenser/evaporator are divided in two further vessels. The condenser/evaporator has one part (3), in which the heat exchanger (3.3) thereof is placed, and one collecting part (4), in which the volatile liquid in its condensed shape is stored. In the same way, the reactor has a part (1), in which the heat exchanger (1.3) and the filter (1.2) thereof are placed, and a collecting part (2), in which solution of the active substance in the volatile liquid is stored. By this division only a small portion of the current mass has to change its temperature in the switching operations that hence can be made significantly more rapidly. A large gain in cooling efficiency can be obtained in an installation having two main units. Furthermore, no valves are required on the vacuum side.

Description

RELATED APPLICATION

This application claims priority and benefit from Swedish patent application No. 0303304-0, filed Dec. 8, 2003, the entire teachings of which are incorporated herein by reference.

TECHNICAL FIELD

The present invention relates to a chemical heat pump working according to the hybrid principle and a sprayer or distributor for a heat exchanger, in particular a spreading device for spraying liquid over a heat exchanger in a chemical heat pump.

BACKGROUND OF THE INVENTION

A chemical heat pump is disclosed in the published International patent application WO 00/37864 which works according to a special process, herein called the hybrid principle, the hybrid method or the hybrid process.
In the previously known heat pump all energy is stored in a main unit. This main unit always works in an equilibrium state and thus is always hot. Withdrawal of chill or heat for the AC system of the house is made in a so called slave unit working quite independently of the main unit. Provided that energy is stored in the main unit water and loaded substance can be transferred to the slave unit which can then produce heat or chill at all times of day and night when there is a need for it. Heat for hot water is at night taken directly from the main unit which obviously is always hot.
This machine requires for functioning at least three valves for communication between the main unit and the slave unit. However, valves in installations that use media which can crystallize to a solid state can have an unsafe function and generally provide a risk of leaks. Therefore, there is a need for reducing the number of valves.
Generally the prior machine includes a first vessel, called accumulator or reactor, containing a substance which can exothermically absorb and endothermally desorb a sorbate. The first vessel is coupled to another vessel, called condenser/evaporator, through a pipe conduit. The second vessel works as a condenser for condensing gaseous sorbate to liquid sorbate while endothermally desorbing the substance in the first vessel and as an evaporator of liquid sorbate to gaseous sorbate while exothermally absorbing sorbate in the substance in the first vessel. The substance in the first vessel is in direct contact with a first heat exchanger in it which can in turn, through a liquid flow, be provided with heat from or supply heat to the ambient atmosphere. The liquid in the condenser/evaporator is in the same way in direct contact with a second heat exchanger in it, to or from which heat can be supplied or withdrawn from or to the ambient atmosphere, respectively, through a liquid flow. In order that the heat pump will be capable of working according to the hybrid-principle the first heat exchanger together with the substance in the solid state thereof are contained in a close-meshed net or filter inside the first vessel. Solution forming the liquid form of the substance exists at the lower part of the first vessel and is collected in a free space next beneath the first heat exchanger. From this space, by means of a conduit and a pump, solution can be sprayed over the first heat exchanger.

SUMMARY OF THE INVENTION

It is an object of the invention to provide a chemical heat pump working according to the hybrid principle that has a reduced number of interior valves.
It is another object of the invention to provide an installation including a chemical heat pumps working according to hybrid principle, the installation having a high efficiency.
A chemical heat pump working according to the hybrid principle generally includes a reactor part in which, in the loading stage, the active substance in a dissolved state passes to a solid state and remains in the reactor part, the volatile liquid then being desorbed and at the same time/thereafter being vaporized, and in which, in the unloading stage, the active substance in its solid state absorbs vapor of the volatile liquid and passes to a dissolved state. Furthermore, the chemical heat pump includes a condenser/evaporator part in which, in the loading stage, vapor of the volatile liquid is received from the reactor part and is condensed to a liquid state and remains in the condenser/evaporator part, and in which, in the unloading stage, at least part of the volatile liquid is vaporized and the formed vapor is transferred to the reactor part.
Furthermore, generally a chemical heat pump or thermodynamical machine having no valves at the vacuum side is provided. The principle is using two identical main units. Each main unit consists of a reactor and a condenser/evaporator integrated in the same container. One of the main units can then be loaded while the other one for example is producing chill. One of the disadvantages of this principle is the large amount of energy required at the turnarounds or direction changes of the process. The unit which has been loaded, is to be cooled, and the unit that has been producing chill is to be heated. Therefore, such a turn-around operation requires a long time period and the energy that is transferred in the cooling process is the main loss in the system. In tests, it has been proved that it takes about 30-50 minutes. During this time the machine is inactive and cannot cool the house/apartment.
Therefore, to improve this situation each one of reactor and condenser/evaporator can be divided in two further vessels. The condenser/evaporator has a part in which the heat exchanger is placed and a collecting part in which the volatile liquid in its condensed form, i.e. usually water, is contained. Also the reactor has a part in which the heat exchanger and the filter are placed and a collecting part in which solution of the active substance in the volatile liquid is stored.
By this division only a minor portion of the current mass of substance has to change its temperature in a turn-around operation. Hence, the turn-around operation is performed significantly more rapidly and is according to tests finished in less than 10 minutes. A large improvement in cooling efficiency can be obtained in the practical application using two main units in which, in the intended operating mode, it in principle never happens that one of the main units is totally unloaded and the other main unit is totally loaded.
Generally thus, a chemical heat pump is provided, working with an active substance, usually a suitable metal salt, and a volatile liquid, usually water, that can be absorbed and desorbed by the active substance at respective temperatures, between which there is a substantially constant temperature difference, so that, inside the interval between the temperatures, the active substance gradually passes from being in a state dissolved in the volatile liquid to a solid state, i.e. usually a crystalline state, when the volatile liquid is desorbed. More particularly the volatile liquid can be absorbed by the active substance at a first temperature and desorbed by the substance at a second higher temperature so that the active substance at the first temperature has a solid state, from which the active substance, when absorbing the volatile liquid and the vapor phase thereof, immediately passes partially into a liquid state or solution state and at the second temperature has a liquid state or is in a solution state, from which the active substance, when the volatile liquid disappears therefrom, in particular the vapor phase thereof, immediately passes partly to a solid state.
Furthermore, the chemical heat pump includes a reactor part having a first heat exchanger located therein. The active substance stays all the time in the reactor part and therein passes between its solid state and a state dissolved in the volatile liquid. Furthermore, a condenser/evaporator part having a second heat exchanger placed in it is provided. In the condenser/evaporator part, all the time only volatile liquid is staying but in a varying amount and in this part, it can be vaporized and condensed. A passage or pathway for only vapor/gas extends between the reactor part and the condenser/evaporator part and connects them. A distributor or a sprayer can be provided in the reactor part to make the active substance in a liquid, i.e. in a dissolved, state pass in contact with the first heat exchanger and the solid substance. In the same way a distributor or sprayer can be provided in the condenser/evaporator part to make the volatile liquid in its liquid state to pass in contact with the second heat exchanger.
Then, in the reactor part:

in the loading stage, the active substance in its dissolved state passes to a solid state and remains in the reactor part, the volatile liquid then being desorbed and at the same time/thereafter vaporized, and
in the unloading stage, the active substance in its solid state absorbs vapor of the volatile liquid and passes to a dissolved state, and in the condenser/evaporator part:
in the loading stage, vapor of the volatile liquid is received from the reactor part and is condensed to a liquid state and remains in the condenser/evaporator part,
in the unloading stage, at least part of the volatile liquid is vaporized and the formed vapor is transferred to the reactor part.

Advantageously, the reactor part is divided in two separate vessels, i.e. a reactor vessel to perform the absorption/desorption of the volatile liquid in/from the active substance and to contain or store the active substance when it after the desorption is in its solid, non-dissolved state, and a collecting vessel for the reactor for collecting and storing the active substance when it is in a state dissolved in the volatile liquid. Thereby it can be achieved that the temperature of the material that is contained or stays in the collecting vessel for the reactor is not dependent on the temperature of the desorption of the volatile liquid and for vaporizing it in the reactor vessel.
In the same way, advantageously, the condenser/evaporator part can be divided in two separate vessels, i.e. a condenser/evaporator vessel to perform the vaporizing/condensing of the quantity of the volatile liquid staying in the condenser/evaporator part, and a collecting vessel for collecting the volatile liquid in the liquid/condensed state thereof during the unloading stage of the chemical heat pump and for storing the volatile liquid during the loading stage of the chemical heat pump. Thereby it can be achieved that the temperature of the material staying or being contained in the collecting vessel for the condenser/evaporator part is not dependent on the temperature of vaporizing/condensing in the condenser/evaporator vessel.
Furthermore, the collecting vessel for the reactor is advantageously located at a level beneath the reactor vessel and in the same way the collecting vessel for the condenser/evaporator part can be located at a level beneath the condenser/evaporator vessel. The collecting vessel for the evaporator/condenser can be located directly below the reactor collecting vessel. The condenser/evaporator vessel is advantageously located directly on top of or above the reactor vessel separated by only a partition wall. The gas/vapor passage/pathway is located in this partition wall.
Generally, the reactor part and the condenser/evaporator part can be formed by spaces in a single container that by suitable interior walls, also called partition walls, is divided in different parts.
Advantageously, a first pump is arranged to circulate the active substance. Then the first pump is connected to the reactor collecting vessel to make the active substance in the dissolved state thereof flow over the first heat exchanger and it is also connected to an outlet of the reactor vessel. Thus, liquid flows and levels can be balanced without arranging any exterior regulation or control. Hence, the first pump is provided to pump, in the loading stage, liquid from the reactor collecting vessel to the distributor or sprayer in the reactor vessel. It can in the loading stage also pump liquid from the collecting vessel for the evaporator/condenser to the distributor or sprayer in the reactor vessel.
A second pump can be provided to pump, in the unloading stage, liquid from the collecting vessel for the evaporator/condenser to the condenser/evaporator vessel, to the distributor or spraying device for the condenser/evaporator part, that is placed in the condenser/evaporator vessel at the second heat exchanger.
Furthermore, the condenser/evaporator vessel can include an emergency liquid vessel that has a rather restricted volume and is connected and located to be capable of receiving only a limited amount of condensate of the volatile liquid. The emergency liquid vessel then is connected, through a connection path including a vapor lock, to an outlet conduit of the first pump containing a circulating flow of the active substance in the dissolved state thereof. The temperature difference between the active substance in the circulating flow and the condensate in the emergency liquid vessel can thereby prevent a flow from the emergency liquid vessel into the outlet conduit in normal operation of the chemical heat pump. Then, the connection path between the emergency liquid vessel and the outlet conduit can contain a check valve arranged to prevent unintended flow of the active substance in the dissolved state thereof to the emergency liquid vessel.
A filter or net can be placed in the reactor part below the first heat exchanger to retain the active substance in the solid state thereof and the filter or net is then advantageously designed as a basket open upwards and is thus placed in the reactor vessel. The filter or net can be designed to include an overflow device to let solution containing possibly solid substance pass directly to the collecting vessel of the reactor in the case where solution is supplied and spread over the heat exchanger of the reactor with a too large velocity.
Furthermore, another connection path of passive type, i.e. a pipe conduit having no pump, between the reactor vessel and the reactor collecting vessel can be established, as controlled or selected, to obtain a mixing between amounts of the active substance in the dissolved state thereof that are staying in the reactor vessel and in the reactor collecting vessel. Thus, the flow from the reactor vessel to the collecting vessel thereof through this connection path occurs only due to gravity. A control unit can be provided to establish this connection between the reactor vessel and the reactor collecting vessel depending on the temperature in the reactor vessel so that the connection is established when this temperature is low. Furthermore, the control unit can include a temperature sensor in which a temperature variation corresponds to a change of the position of a mechanical part or in which a temperature variation is converted to mechanical work, in particular including a part of a composite metal/bimetal or a memory metal or a part containing some suitable wax or a gas.
In the heat pump two sprayers are used, one sprayer for spreading a solution in the reactor part and one for spraying water in the condenser/evaporator part. These sprayers spray liquid over surfaces of the respective heat exchanger and they can be designed as simple shower devices or as rotating sprayer arms. In sprayers having a rotating sprayer arm driven to be rotated due to the outflow of liquid, i.e. due to a reaction force, it is obtained, in the case that the flow is varying and sometimes very small, which can occur in particular in the reactor part, that the sprayer arm does not obtain any rotation movement but during more or less long time periods stands on the same place and that thus all liquid flowing out then only moistens the same surfaces of the heat exchanger. Instead, in order to obtain in such cases a rotation movement and distribution of liquid over different surfaces of the heat exchanger, gravity can be used. Generally, such a spraying device can be used for spraying liquid over surfaces of an arbitrary heat exchanger.
A sprayer driven by gravity includes generally at least one sprayer arm that has at least one outlet opening for liquid and a bearing device at which the sprayer arm is mounted to be capable of rotating about a substantially vertical sprayer shaft in a rotation movement produced by the flow of the liquid. The sprayer arm can be substantially horizontal or form some small angle to the horizontal plane. When liquid passes out of the outlet opening in the sprayer arm, in a special embodiment a vane or scoop device is affected that drives the sprayer arm to be rotated around the rotation shaft. Particularly, the vane or scoop device can include a vane or scoop wheel that has a rotation shaft and that includes at least one vane or scoop that is located so that it receives liquid that is flowing out of the outlet opening. By the weight of the liquid received in the vane or scoop, the vane or scoop wheel is made to rotate about the rotation shaft and then the received liquid is emptied out over the surfaces of the heat exchanger located below the sprayer. Then, a driving device is connected to the rotation shaft to make, in the rotation of the vane or scoop wheel, the sprayer arm rotate about the rotation shaft of the sprayer arm.
Advantageously, the vane or scoop or vanes or scoops are arranged substantially straight below the sprayer arm so that the vane or scoop or vanes or scoops in the rotation movement of the sprayer arm perform the same rotation movement as the sprayer arm around the rotation shaft. Furthermore, each vane or scoop is preferably elongated and has a groove shaped space extending in a direction away from the rotation shaft of the sprayer arm. A driving wheel can be connected to the rotation shaft of the vane or scoop wheel to cooperate with a fixedly arranged circular path. In the rotation of the vane or scoop wheel and the rotation shaft, the driving wheel is driven to rotate and then runs along the path, whereby, by the friction against the circular path, the driving wheel is moved along the path and thereby rotates the vane or scoop wheel about the rotation shaft of the sprayer arm. The sprayer arm can suitably include a pipe having a longitudinal slot or having at least one hole forming the outlet opening. This slot or hole can then be arranged at the topmost part of the pipe.
Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the methods, processes, instrumentalities and combinations particularly pointed out in the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

While the novel features of the invention are set forth with particularly in the appended claims, a complete understanding of the invention, both as to organization and content, and of the above and other features thereof may be gained from and the invention will be better appreciated from a consideration of the following detailed description of non-limiting embodiments presented hereinbelow with reference to the accompanying drawings, in which:
FIG. 1 a is a schematic of a chemical heat pump,
FIG. 1 b is a schematic of an alternative embodiment of a chemical heat pump,
FIG. 2 is a block diagram of an air conditioning installation driven by chemical heat pumps,
FIG. 3 a is a schematic of a sprayer, and
FIG. 3 b is a schematic view of the sprayer according to FIG. 3 a taken from the end of a sprayer arm.

DETAILED DESCRIPTION

In FIG. 2 the most important parts of an air conditioning installation driven by two alternatingly working, identical main units 200 are shown. Each main unit consists of a reactor and a condenser/evaporator arranged in a container. The main units include upper and lower heat exchangers 210, 220 for the reactor and the condenser/evaporator, respectively. The upper heat exchangers can through threeway valves 230 be connected to either elements AC intended to cool for example a house/apartment or an office, or to a cooling medium cooler OC. The lower heat exchangers can through threeway valves 240 be connected either to the cooling medium cooler OC or elements which are heated in some suitable way, such as solar panels SP. By a suitable setting of the threeway valves one of the main units can be loaded while the other one for example produces chill in the elements AC. It has turned out that large energy amounts are consumed in changes or in so called turn-arounds of the system when one of the main units, from producing chill, passes to be loaded while the other main unit passes from being loaded to start producing chill. These turn-around operations require a long time in conventional designs of the main units. A chemical heat pump unit requiring a shorter time for turn-around operations will now be described.
Thus, in FIG. 1 a schematically a first embodiment of a chemical heat pump or a thermodynamic machine for producing chill or heat is shown, which is constructed to generally work according to the process described in the above-mentioned International patent application WO 00/37864. The machine includes as a main component a vacuum tight container 100 which is divided in different parts or vessels, also called chambers, by a multitude of partition walls. A reactor vessel 1, also called only a reactor, is by a weakly sloping, flat and impermeable partition wall 110 at its bottom separated from a reactor collecting vessel 2, also called first collecting vessel. The reactor vessel 1 continues at its upper end into the condenser/evaporator vessel 3, also called only condenser/evaporator, and is separated therefrom by a partition wall 120 that has a horizontal bottom in the embodiment shown in the figure and at its central part continues into a gas pipe 3, 4 that extends upwards from this partition wall. The reactor collecting vessel 2 is in the same way as the reactor vessel separated, by a weakly sloping, flat and impermeable partition wall, at its bottom from a collecting vessel 4 for the condenser/evaporator, also called second collecting vessel.
In the reactor vessel 1 a heat exchanger 1.3 is provided, also called heat exchanger unit, and a corresponding heat exchanger 3.3 is provided in the condenser/evaporator vessel 3. Furthermore, in the reactor vessel 1 a filter 1.2 is placed, also called a reactor filter and generally called a separating device, placed below the heat exchanger 1.3 to separate and collect solid substance.
It is now assumed that the machine in the start thereof is unloaded, i.e. that no active substance in its solid state exists in the machine.
Then, the active substance exists as a solution in the collecting vessel 2 of the reactor. A valve 2.3 connected in a pipe conduit 2.2 between a first bottom outlet 1.7 at the bottom portion of the reactor vessel 1 and the reactor collecting vessel 2 is closed. Only a minor amount of the volatile liquid, usually water, is staying in the collecting vessel 4 of the condenser/evaporator that is located lowermost in the container 100. A first pump P1 is started while a second pump P2 is shut off. These pumps are also called sprayer pumps, for the heat exchanger 1.3, 3.3, of the reactor and of the condenser/evaporator, respectively.
Heat is supplied to the heat exchanger 1.3 of the reactor, such as from the solar panels SP, see FIG. 2, and the heat exchanger 3.3 of the condenser/evaporator is cooled such as by the cooling medium cooler OC.
When the first pump P1 is started, solution flows through a bottom outlet 2.1 from the lower part of the collecting vessel 2 of the reactor, through a pipe conduit 132 having a check valve 2.4 connected therein, to the inlet of and through the first pump, through the outlet pipe 131 of the first pump and through an inlet pipe 1.6 up to a sprayer 1.4 located in the top portion of the reactor vessel 1 to be spread over the surfaces of the heat exchanger 1.3 of the reactor. The sprayer can be designed as a conventional rotating arm that is centrally mounted to rotate, has a central supply and rotates due to the reaction force derived from outflowing liquid. The sprayer arm can then be provided with a plurality of small outlet holes or alternatively with two large outlet openings in each end of the arm. These openings are then suitably placed at different distances from the central mounting of the sprayer arm 4.1, so that all surfaces of the heat exchanger 1.3 of the reactor can be reached by the flow generated by the first pump P1.
Thus, the solution is spread by the sprayer 4.1 over the heat exchanger 1.3 of the reactor and solution therefrom flows through the filter 1.2 and a second bottom outlet 1.5 at the bottom of the reactor vessel 1, from the reactor vessel through a pipe conduit 133, extending from this bottom outlet to the inlet of the first pump P1, again back to the first pump. This solution that is now in circulation in the reactor vessel is rapidly heated by the heat exchanger 1.3 and is thereby loaded. In the loading process, water vapor flows out of the reactor vessel 1 through the gas pipe 3.4 to the condenser/evaporator vessel 3, in which the water vapor is condensed on the surfaces of the heat exchanger 3.3 of the condenser/evaporator and through an outlet 3.5 of the condenser/evaporator vessel, arranged at the bottom of this vessel, that is formed by the partition wall 120, through a pipe conduit 135 flows downwards and from this pipe conduit into the collecting vessel 4 of the condenser/evaporator through a further pipe conduit 136 connected to a bottom inlet/outlet 4.1 for this collecting vessel. The amount of solution in the reactor vessel is then reduced, and then further new solution continuously trickles in from the collecting vessel 2 of the reactor through the conduit 132 and the check valve 2.4 to the inlet of the first pump P1 to be pumped on. Then, the solution is becoming more and more concentrated and the dissolved active substance gradually passes to its solid state, i.e. crystals are formed, which are collected by the reactor filter 1.2 having the shape of a basket and located in the reactor vessel 1.
The check valve 2.4 prevents hot solution from entering, due to swinging motions caused by pressure differences between the collecting vessel 2 of the reactor and the reactor vessel 1, the collecting vessel 2 of the reactor from the outlet 1.5 of the reactor vessel through the pipe conduits 132, 133 which are both connected to the inlet of the first pump P1. The intention is that the collecting vessel 2 of the reactor will remain cold. In that way the loading process is being continued until the collecting vessel 2 of the reactor is emptied of solution and the filter 1.2 in the reactor vessel 1 contains substantially all active substance in the machine which is then in the solid state of the active substance.
Between the reactor vessel 1 and the reactor collecting vessel 2 a pipe 1.1 extends that is for example centrally located and is intended to equalize pressure differences between these vessels and that from the upper wall of the reactor collecting vessel, i.e. from the partition wall 110, extends some distance upwards to the interior of the reactor vessel, such as up to approximately the center thereof. The reactor filter 1.2 can, as shown in the figure, be designed as a basket having an annular space that is open upwards, for receiving the crystals of the active substance, i.e. of the solid state thereof. Then, the centrally placed pipe 1.1 extends in the centrally located raised portion of the filter up to and mouths somewhat below a large hole 1.8 in the filter, for example made in a metal plate arranged there. Solution can flow directly back through the hole 1.8, the second bottom outlet 1.5 of the reactor vessel and the conduit 133, to the first pump P1, in the case where the filter 1.2 is not capable of letting through solution, through the small holes or meshes in its bottom and its sides, with a sufficiently high velocity compared to the velocity with which the first pump P1 is pumping solution.
The condensed water has finally been collected in the second collecting vessel 4. When this vessel, soon before the loading is finished, is full, the level rises in a pipe 135 extending between the inlet of the second pump P2 and a bottom outlet 3.5 of the lower part of the condenser/evaporator vessel 3. After some time the level is so high that condensed water enters the condenser/evaporator vessel 3 through the bottom outlet 3.5. When the level reaches a predetermined height in the condenser/evaporator vessel 3, condensed water flows back from the condenser/evaporator vessel through a overflow pipe 3.9 to the upper portion of the reactor vessel 1. The loading stage is now finished but heat effect from the solar panel can still be received. A sensor, not shown, can be placed at the inlet of the overflow pipe 3.9 into the reactor vessel 1. 1, where the overflow pipe normally is hot. The sensor detects the temperature depression occurring when water, when in a full total loading state, arrives flowing through the overflow pipe 3.9 and cools this pipe, and the sensor can thereby provide a signal that indicates a full loading of the heat pump.
Now the process can be turned the other way around.
The heat exchanger 1.3 of the reactor is now cooled and the heat exchanger 3.3 of the condenser/evaporator 3 is connected to the AC system of the house. The second pump P2 is started. Possibly remaining solution in the reactor vessel 1 is cooled together with the salt, i.e. the crystals of the active substance or the solid state of this active substance, that stays in the filter 1.2. Water is pumped by the second pump P2 through a pipe conduit 137 to flow over the heat exchanger 3.3 in the condenser/evaporator vessel, and then it first rises from the pipe conduit to an inlet 3.6 at the topmost portion of the condenser/evaporator vessel 3. From the inlet the water arrives to the emergency liquid vessel 3.3 that is centrally arranged in the condenser/evaporator vessel, has a relatively small volume and thus can receive a limited water amount. Further, the water flows through overflow holes 3.8 in surrounding partition walls 150 that define the emergency liquid vessel, from this vessel 3.2 over to the sprayer vessel 3.1 arranged at the side of the emergency liquid vessel, wherefrom the water, through openings in the bottom of the spray vessel, flows over the heat exchanger 3.3 of the condenser/evaporator. The spray vessel with its bottom openings works as a sprayer device of the condenser/evaporator vessel 3 and is in principle a shower device.
In the case where the spray vessel 3.1 is not capable of receiving all the water, surplus water flows through an overflow pipe 3.11, that extends from the very topmost portion of the condenser/evaporator vessel 3 inside the spray vessel 3.1 down through the condenser/evaporator vessel to mouth at the heat exchanger 3.3 located therein. Through the outlet 3.5 of the condenser/evaporator vessel 3, thereafter the water flows again through the pipe 135 to the inlet of the second pump P2. When the reactor vessel 1 is cooled, a ball valve 2.3 arranged in the pipe conduit 2.2 between the first bottom outlet 1.7 of the reactor vessel and the reactor collecting vessel 2 is opened, the two vessels 1 and 2, the reactor vessel and its collecting vessel, then being made to form practically a single main reactor or reactor unit. The salt in the filter 1.2 is slowly dissolved and more and more solution is collected in the collecting vessel 2 of the reactor. The process continues as long as the cooling temperature which is produced in the medium that flows out to the AC system is acceptable.
The ball valve 2.3 is controlled depending on the temperature of the reactor vessel 1, such as by using a temperature sensor/control unit 1.9 placed at the bottom of the reactor vessel, i.e. at the top surface of the partition wall 1.10. This temperature sensor/control unit can generally include a sensor in which a temperature variation corresponds, in a way not shown, to a change of the position of a mechanical part or in which the temperature variation is converted to mechanical work, in particular including a part of bimetal or of memory metal or a part containing wax or gas, so that the ball valve 2.3 can be directly influenced in a mechanical manner.
In the case of interruption of the electrical power supply the pumps P1, P2 will stop. Then the active substance in remaining solution in the pipe conduits and in the first pump P1 has the risk of being precipitated as crystals. To prevent it, water from the emergency liquid vessel is used. During normal operation the pumping level in the outlet pipe 131 from the first pump P1 is such that the pump level is somewhat above the level of the inlet pipe 1.6 of the sprayer 1.4 in the reactor vessel 1. Water from the emergency liquid vessel 3.2 cannot then in normal operation flow down through a cleaning pipe 3.10, extending from the bottom portion of the emergency liquid vessel to the inlet pipe of the sprayer of the reactor vessel, due to a vapor lock 3.12, formed by a downwards going loop in the pipe 3.10 in an otherwise horizontal portion of this pipe. A check valve 3.7, connected in the cleaning pipe, prevents solution from entering the condenser/evaporator vessel 3 such as due to pressure shocks. After the first pump P1 has stopped, due to for example interruption of the current supply, water flows from the emergency liquid vessel 3.2 through the check valve 3.7 and the cleaning pipe 3.10 and the vapor lock thereof down through the outlet conduit 131 of the first pump P1 to the first pump and cleans this conduit and the first pump from salt solution.
The same procedure can be used to intentionally stop the first pump to perform so called rinsing. It means that water from the condenser/evaporator vessel 3.2 intentionally is made to flow back to the reactor vessel 1 through the cleaning pipe 3.10 and from this pipe to the inlet pipe 1.6 and the sprayer 1.4 for the heat exchanger 1.4 of the reactor to remove salt residues that have accumulated after a long time of operation.
In the heat pump described above pipes located at the exterior are provided in which hot saturated solutions flow. To prevent crystallization in these pipes and pumps, heating jackets can be used. They can for example consist of copper pipes having a shield of aluminum foil and on top of it common porous heat isolation. The copper pipes can be heated by the energy source of the heat pump at daytime and by a separate electrical resistive immersion heater at night. Instead of such jackets, electrical resistive heating strips with foils wrapped around them can be used. In the somewhat modified embodiment of a heat pump shown in FIG. 1 b the solution pump, i.e. the first pump P1, is placed below the reactor part and particularly directly below the reactor collecting vessel 2, so that the pumping house, the inlet pipe and the outlet pipe thereof are located inside the container 100. Thus, these pipes obtain the same temperature as the solution and crystallization in the pipes is prevented.
Crystals that are made to migrate in the loading stage of the heat pump and at the turn-around thereof can create problems in the first pump P1 and in the sprayer 1.4 in the reactor vessel 1, which in the worst case can stop working. In the embodiment shown in FIG. 1 b an extra filter 1.10 is provided, also called pump filter of the reactor vessel, mounted at the inlet of the first pump P1. The inlet of this pump is made as a pipe 1.11 that is a continuation of the reactor vessel 1 and extends from the bottom 110 thereof centrally down through the whole of the reactor collecting vessel 2. The bottom of the reactor vessel can be designed as a low frustrum of a cone or as a funnel for achieving that liquid more easily flows away towards the central pipe 1.11. The solution filtered in the primary reactor filter 1.2 flows down through this pipe 1.11 that has double walls to provide a heat isolation against the solution in the reactor collection vessel 2. The pipe contains the extra filter 1.10 that separates the solution flowing down from the reactor from the inlet of the pump. This filter is of the same type as the reactor filter 1.2. In the same way as in the first embodiment the first pump P1 collects solution both from the reactor vessel 1 and from the collecting vessel 2 thereof Also the solution collected from the collecting vessel 2 is filtered by the fact that it has to pass another filter 2.5, called the pump filter of the reactor vessel. This filter surrounds the inlet pipe 1.11 of the first pump P1. From the space between this additional filter and the inlet tube 1.11 liquid can flow through the outlet 2.1 and the check valve 2.4 to the inlet of the first pump.
In the embodiment of FIG. 1 a it can occur that crystals can block the valve 2.3 that controls a flow directly from the reactor vessel 1.2 to the collecting vessel 2 thereof, and/or the conduit in which this valve is connected, also in the case where the valve and the conduit have jackets in the same way as described above. The valve 2.3 is completely moved into the vacuumtight container 100 in the embodiment shown in FIG. 1 b. There the valve is designed as a slide valve that is controlled by being moved forwards and backwards. This movement is conveyed through a screwing movement magnetically communicated from the outside, from a motor 2.7 placed outside the container 100.
The water staying in the collecting vessel 4 of the condenser/evaporator after the loading stage can in the embodiment of the heat pump according to FIG. 1 a have been heated due to the direct contact with the collecting vessel 2 of the reactor through the simple partition wall 130, and thus that a too large pressure difference is created between the spaces in the collecting vessel 4 and the condenser/evaporator vessel 3 when the latter vessel is cooled. The water in the collecting vessel 4 can be pressed up to a higher level in the condenser/evaporator vessel 3, water then flowing either through the overflow pipe 3.9 or directly through the gas pipe 3.4 down to the reactor vessel 1. This results in the fact that valuable loaded substance device is lost. The simple partition wall 130 between the collecting vessels 3, 4 can then be replaced with a double partition wall 160, 170 as illustrated in FIG. 1 b. Thereby, the collecting vessels are mechanically separated by a heat isolating space 2.6. Furthermore, the upper opening of the gas pipe 3.4 has been placed higher than in the embodiment of FIG. 1 a. In addition, in the embodiment shown in FIG. 1 b no overflow pipe 3.9 and no temperature sensor at this pipe are provided. The loading level is instead indicated by a floating body 4.2.
The outlet 3.5 of the lowermost portion of the condenser/evaporator vessel 3 should be connected at some distance of the heat exchanger 3.5 in this vessel. Otherwise, sound bangs can be obtained in the pipe that extends from this outlet, in particular when unloading the heat pump. These sound bangs are generated by gas bubbles being transported down in the pipe and imploding with bangs. As shown in FIG. 1 b, a sufficient distance can be obtained by the fact that the partition wall 120 between the condenser/evaporator vessel 3 and the reactor vessel 1 is given some slope and the outlet 3.5 is placed at the lowest part of this partition wall.
The sprayer in the condenser/evaporator vessel 3 can instead of being the type stationary shower include a usual sprayer arm 3.13 that is centrally mounted to rotate in this vessel, centrally receives liquid from the second pump P2 and rotates, caused by the flow generated by this pump, see FIG. 1 b. However, a sprayer 4.1 for the heat exchanger 1.3 for the reactor vessel 1 designed as such a rotating arm can often stop, particularly during the final period of the loading stage, when the flow of the solution is significantly reduced.
Another type of spraying device for the reactor vessel 1 which is more independent of the size of the flow for its rotation is illustrated in FIGS. 3 a and 3 b. The liquid pumped up to the sprayer through the central inlet pipe 1.12 is distributed in a rotatably mounted distributor unit 31 at the upper end of the inlet pipe to two radially arranged, diametrically opposed distributor pipes 33, also called sprayer arms. The distributor pipes have at their uppermost portions slots 35 through which the pumped liquid flows out over the exterior sides of the distributor pipes and therefrom down to a vane or scoop wheel 17 arranged directly beneath the distributor pipes, the vane or scoop wheel also extending in radially opposite directions from the central inlet pipe 1.22. Instead of slots, as outlet openings of the distributor pipes, suitably arranged holes, not shown, can be provided. The slots 35 and such holes can, as is shown, be located at the topmost portions of the distributor pipes but they can also have some other suitable place, such as at a side of or at the lower part of the distributor pipes. The vane or scoop wheel 37 has at each side of the central inlet pipe 1.12 at least one but better two and as is shown in the FIG. 3 b preferably four elongated, radially arranged vanes or scoops 39, which include elongated spaces having a groove shape and are mounted to rotate it about the shaft 41 of the vane or scoop wheel, this shaft located approximately along a diameter, quite close to the inlet pipe 1.12. This shaft is at its ends mounted at horizontal holder plates 42 that are also attached to the outermost ends of the distributor pipes 33. In the rotating movement of the vane or scoop wheel 37 that is obtained when the respective ones of it vanes or scoops are gradually filled with liquid and move down due to gravity, also a driving wheel 43 rotates that is rigidly attached to one end of the shaft 41 of the vane or scoop wheel. This driving wheel runs against a circular horizontal path 45, also called an annular support rail, that is rigidly mounted to the reactor vessel 1, and the driving wheel thereby causes, due to the friction of the driving wheel against the path, a rotating movement of the whole spraying unit about the vertical, central shaft through the inlet pipe 1.12. The liquid staying in the vanes or scoops 39 is then emptied stepwise over new surfaces of the heat exchanger during the rotation of the sprayer arms around in the reactor vessel 1. Such a sprayer can obviously also be used in the condenser/evaporator vessel 3 and in other devices, in which a spreading or distribution of liquid from a varying flow is desired over a multitude of surfaces placed at each other.
For a sudden stop of operation, as has been mentioned above, problems associated with crystallization can occur. For example interrupts in the electrical current or power supply, all pumps in the system stop and substance and solution cool. The solution to this is to make water flow back from the condenser/evaporator vessel 3 to the reactor vessel 1, this water obtained from the emergency liquid vessel 3.2. In the embodiment illustrated in FIG. 1 b the emergency liquid vessel is placed outside the vacuumtight container 100 and is there connected in the conduit from the second pump P2 to the sprayer 3.13 in the condenser/evaporator vessel 3. From the emergency liquid vessel a conduit including a magnet valve 3.14 extends directly down to the inlet pipe 1.12 of the reactor vessel, said-pipe also being the outlet pipe of the first pump P1 and extending centrally through the extra filter unit 1.10. After a stop of operation this valve is opened.
In the bottom of the first pump P1, also called the solution pump, an electrical emergency heating element 108 is arranged, that can dissolve crystals which can be formed during long-time interrupts.
While specific embodiments of the invention have been illustrated and described herein, it is realized that numerous additional advantages, modifications and changes will readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details, representative devices and illustrated examples shown and described herein. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents. It is therefore to be understood that the appended claims are intended to cover all such modifications and changes as fall within a true spirit and scope of the invention.
List of Components

1: Reactor vessel
1.1: Pressure equalizing pipe between top wall in reactor collecting vessel and the interior of reactor vessel
1.2: Reactor filter
1.3: Heat exchanger for reactor in reactor vessel
1.4: Sprayer in reactor vessel
1.5: Second outlet of reactor vessel to first pump P1
1.6: Inlet pipe of reactor vessel
1.7: First outlet of reactor vessel to reactor collecting vessel
1.8: Overflowing hole located topmost in central portion of reactor filter
1.9: Temperature sensor/Control unit at the bottom of reactor vessel
1.10: Extra filter=pump filter of reactor vessel
1.11: Centrally arranged, double wall outlet pipe of reactor vessel towards inlet of first pump P1
1.12: Central inlet pipe of reactor vessel=outlet pipe of first pump P1 to sprayer in reactor vessel
2: Reactor collecting vessel
2.1: Outlet of reactor collecting vessel
2.2: Pipe from first outlet of reactor vessel to reactor collecting vessel
2.3: Ball valve in pipe from first outlet for reactor vessel to reactor collecting vessel
2.4: Check valve in pipe from outlet of reactor collecting vessel to inlet of first pump P1
2.5: Pump filter for reactor collecting vessel
2.6: Heat isolating space below the bottom of reactor collecting vessel and above top wall in collecting vessel for condenser/evaporator
2.7: Valve motor
3: Condenser/evaporator vessel
3.1: Sprayer vessel
3.2: Emergency liquid vessel
3.3: Heat exchanger of condenser/evaporator
3.4: Gas pipe between condenser/evaporator vessel and reactor vessel
3.5: Outlet of condenser/evaporator vessel
3.6: Inlet of condenser/evaporator vessel with mouth in emergency liquid vessel
3.7: Check valve in pipe from outlet of emergency liquid vessel to inlet pipe of sprayer of reactor vessel
3.8: Overflow holes for emergency liquid vessel
3.9: Overflow pipe from condenser/evaporator vessel to reactor vessel
3.10: Cleaning pipe from outlet of emergency liquid vessel to inlet pipe of sprayer of reactor vessel
3.11: Overflow pipe from sprayer vessel to main portion of condenser/evaporator vessel
3.12: Vapor lock in horizontal portion of cleaning pipe
3.13: Sprayer of condenser/evaporator vessel
3.14: Valve in outlet of emergency liquid vessel towards main portion of condenser/evaporator vessel
4: Collecting vessel for condenser/evaporator
4.1: Outlet of collecting vessel for condenser/evaporator
4.2: Floating body for level indication
P1: First pump=solution pump for spraying liquid of active substance over heat exchanger in reactor
P2: Second pump=condensate pump for distributing liquid over heat exchanger of condenser/evaporator
31: Distributing unit mounted to rotate at central inlet tube
33: Distribution pipe
35: Outlet slot
37: Vane or scoop wheel
39: Vanes or scoops
41: Shaft of vane or scoop wheel
42: Holder plate for vane or scoop wheel
43: Driving wheel
45: Friction path
100: Vacuumtight container
110: Partition wall
120: Partition wall
130: Partition wall
131: Pipe from outlet of first pump P1 to inlet pipe of reactor vessel
132: Pipe from outlet of reactor collection vessel to inlet of first pump P1
133: Pipe from second outlet of reactor vessel to inlet of first pump P1
135: Pipe from outlet of condenser/evaporator to inlet of second pump P2
136: Pipe from outlet of condenser/evaporator collecting vessel to inlet of second pump P2
137: Pipe from outlet of second pump P2 to inlet of emergency liquid vessel
140: Bottom of sprayer vessel
150: Partition walls defining emergency liquid vessel
160: Bottom of reactor collecting vessel
170: Upper partition wall in collecting vessel of condenser/evaporator
180: Electrical emergency heating element in first pump
200: Main unit
210: Heat exchanger of reactor
220: Heat exchanger for condenser/evaporator
230: Threeway valve
240: Threeway valve
AC: Air conditioning
SP: Solar panel

Claims

1. A chemical heat pump including an active substance and a volatile liquid that can be absorbed and desorbed by the active substance at respective temperatures, between which a substantially constant temperature difference exists, so that within the interval between the temperatures the active substance gradually passes from a state dissolved in the volatile liquid to a solid state when the volatile liquid is being desorbed, the chemical heat pump including:

a reactor part having a beat exchanger located therein, the active substance all the time staying in the reactor part and therein being transferred between a solid state and a state dissolved in the volatile liquid,

a condenser/evaporator part having a second heat exchanger located in it, only the volatile liquid staying in the condenser/evaporator part all the time in a varying amount, the volatile liquid being vaporized and condensed therein, and

a passage/pathway for only vapor/gas between the reactor part and the condenser/evaporator part,

characterized in

that the reactor part is divided in two separate vessels,

a reactor vessel to perform the absorption/desorption of the volatile liquid in/from the active substance and to contain or store the active substance, when it after desorption is in a solid state, and

a reactor collecting vessel for collecting and storing the active substance, when it is in a state dissolved in the liquid,

so that it is achieved that the temperature of the material stored or staying in the reactor collecting vessel is not dependent on the temperature of desorption of the volatile liquid and of vaporizing it in the reactor vessel, and/or

that the condenser/evaporator part is divided in two separate vessels,

a condenser/evaporator vessel to perform vaporizing/condensing of the amount of the volatile liquid staying in the condenser/evaporator part, and

a collecting vessel for collecting the volatile liquid in its liquid/condensed state during unloading the chemical heat pump and for storing it during the loading of the chemical heat pump,

so that it is achieved that the temperature of the material stored or staying in the condenser/evaporator part collecting vessel is not dependent on the temperature of vaporizing/condensing in the condenser/evaporator vessel.

2. A chemical heat pump according to claim 1, characterized by a first pump arranged for circulating the active substance, the first pump connected to the reactor collecting vessel to make the active substance in the dissolved state thereof flow over the first heat exchanger and also connected to an outlet of the reactor vessel, so that it is achieved that liquid flows and levels are balanced without any control or regulation.

3. A chemical heat pump according to claim 1, characterized in that the condenser/evaporator vessel includes a emergency liquid vessel for receiving limited amount of condensate of the liquid vessel, the emergency liquid vessel connected, through a connection path including a vapor lock, to an outlet pipe of the first pump containing a circulating flow over the active substance in the dissolved state thereof, the temperature difference between the active substance in the circulating flow and the condensate in the emergency liquid vessel preventing a flow from the emergency liquid vessel into the outlet pipe during operation of the chemical heat pump.

4. A chemical heat pump according to claim 3, characterized in that the connection path between the emergency liquid vessel and the outlet pipe includes a check valve arranged to prevent unintentional flow of the active substance in its dissolved state to the emergency liquid vessel.

5. A chemical heat pump according to claim 1, characterized by a filter or net in the reactor part arranged beneath the first heat exchanger and arranged to retain the active substance in its solid state.

6. A chemical heat pump according to claim 5, characterized in that the filter or net is designed as a basket open upwards for receiving the active substance in the solid state thereof.

7. A chemical heat pump according to claim 1, characterized in that a connection path between the reactor vessel and the reactor collecting vessel can be established according to control or selection to obtain a mixing of amounts of the active substance in the dissolved state thereof that are staying in the reactor vessel and in the reactor collecting vessel.

8. A chemical heat pump according to claim 7, characterized by a control unit for establishing the connection path between the reactor vessel and the reactor collecting vessel depending on the temperature in the reactor vessel, so that the connection is established when this temperature is low.

9. A chemical heat pump according to claim 8, characterized in that the control unit includes a temperature sensor, in which the temperature variation corresponds to a change of the position of a mechanical part or in which the temperature variation is converted to mechanical work, in particular including a part of bimetal or of memory metal or a part including wax or gas.

10. A chemical heat pump according to claim 1, characterized in that the reactor vessel is placed directly on top of the reactor collecting vessel with a simple separating wall.

11. A chemical heat pump according to claim 1, characterized in that the reactor vessel is arranged having its main portion located directly above the reactor collecting vessel and has a narrow part extending downwards through the reactor collecting vessel to an inlet of a first pump, that is arranged for circulating the active substance and receives active substance from the reactor vessel.

12. A chemical heat pump according to claim 11, characterized in by a pump filter in the reactor vessel, the pump filter being arranged in the narrow portion at the inlet of the first pump.

13. A chemical heat pump according to claim 11, characterized in that the first pump is placed at the bottom of the reactor collecting vessel to receive liquid also from the reactor collecting vessel.

14. A chemical heat pump according to claim 13, characterized by a pump filter in the reactor collecting vessel, the pump filter arranged at an outlet of the reactor collecting vessel connected to the inlet of the first pump.

15. A chemical heat pump according to claim 1, characterized by a vacuumtight container that by partition walls, in particular by substantially horizontal partition walls, is divided to form a reactor vessel, a reactor collection vessel, a condenser/evaporator vessel and a condenser/evaporator collector vessel.

16. A chemical heat pump according to claim 15, characterized in that the condenser/evaporator vessel is located directly above the reactor vessel.

17. A chemical heat pump according to claim 15, characterized by in that the collecting vessel for the condenser/evaporator part is placed lowermost in the vacuumtight container.

18. A chemical heat pump according to claim 1, characterized by a sprayer for spraying liquid over surfaces of a heat exchanger, the sprayer being arranged to be rotated over surfaces of the heat exchanger by gravity acting on liquid that passes the sprayer.

19. A sprayer or distributor for spraying liquid over surfaces of a heat exchanger, in particular in a chemical heat pump, including

at least one substantially horizontal sprayer arm having at least one outlet opening for liquid,

a mounting device at which the sprayer arm is mounted to be rotated about a substantially vertical rotation shaft with a rotating movement caused by the flow of the liquid, characterized by a vane or scoop device for receiving liquid from said at least one outlet opening, the vane or scoop device arranged to be made to move, by the gravity acting on the received liquid, and thereby rotate the sprayer arm and the vane or scoop device about the rotation shaft of the sprayer arm.

20. A sprayer according to claim 19, characterized in that the vane or scoop device includes:

a vane or scoop wheel having a rotation shaft and at least one vane or scoop arranged to receive liquid from at least one outlet opening of the sprayer arm and to rotate, by the weight of liquid received in said at least one vane or scoop, about the rotation shaft and then empty out the received liquid, and

a driving device connected to the rotation shaft to make, in the rotation of the vane or scoop heel, the sprayer arm to be rotated about the shaft of the sprayer arm.

21. A sprayer according to claim 20, characterized in that said at least one vane or scoop is located substantially straight beneath the sprayer arm to also perform, in the rotating movement of the sprayer arm, the same rotating movement as the sprayer arm.

22. A sprayer according to claim 20, characterized in that said at least one vane or scoop is elongated including a groove shaped space extending in a direction away from the shaft of the sprayer arm.

23. A sprayer according to claim 20, characterized by

a driving wheel connected to the rotation shaft of the vane or scoop wheel, and

a circular path against which the driving wheel runs, so that in the rotation of the vane or scoop wheel and the rotation shaft the driving wheel is made to rotate and by friction against the circular path moves along the path and thereby rotates the vane or scoop wheel around the shaft of the sprayer arm.

24. A sprayer according to claim 20, characterized in that the sprayer arm includes a pipe having an elongated slot or at least one hole, in particular a slot or a hole arranged at the topmost portion of the pipe.